Synthetic lightsaber crystal, Wookieepedia

I don't need to remind you that a crimson blade doesn't guarantee that the wielder is a Sith, any more than every person strong in the Force is a Jedi. Asajj Ventress was a mere apprentice to Dooku, not a true Sith. A crimson blade can owe to nothing more than a synthetic power crystal. Then crimson is simply a color, like Master Windu's amethyst blade.Roan Shryne A Synthetic lightsaber crystal, commonly referred to as a Synth-crystal, was a type of lightsaber crystal that was artificially creat

Kyber crystal, Wookieepedia

Lightsaber crystal, Wookieepedia

have we ever seen a double bladed lightsaber with two different color blades like this? it's theoretically possible : r/StarWarsEU

Synthetic kyber crystal, Wookieepedia

Did Dooku construct a new lightsaber when he became a sith or did he just bleed his crystal and keep the same hilt? : r/StarWars

Gella Nattai's lightsabers, Wookieepedia

Sith lightsaber, Wookieepedia

Star Wars lightsaber colors, explained - Vox

Wookieepedia - Lightsaber crystals: Adegan crystal, Ankarres Sapphire, Barab ore, Bnar's Sacrifice, Bondar, Bondara's Folly, Compressed energy Durindfire, Enhancement jewel, Eralam